from cinap.

Reference: /n/atom/patch/applied/mul0
Date: Fri Mar 21 00:23:20 CET 2014
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/6c/mul.c	Fri Mar 21 00:23:17 2014
+++ /sys/src/cmd/6c/mul.c	Fri Mar 21 00:23:17 2014
@@ -312,6 +312,11 @@
 	Mparam *p;
 	Node nod, nods;
 
+	if(v == 0){
+		zeroregm(n);
+		return 1;
+	}
+
 	for(i = 0; i < nelem(multab); i++) {
 		p = &multab[i];
 		if(p->value == v)